Email-Worm.Win32.LoveLetter or LoveLetter worm, memorable for its "LOVE-LETTER-FOR-YOU" attachment and "ILOVEYOU" subject line, was one of the early worms to gain a great deal of media attention. It was also one of the first to reportedly reach a multi-billion dollar damage toll, being one of the most dangerous viruses. It would email itself to 50 other Windows computers once a computer is infected.
The virus arrives in an email with the subject line of "ILOVEYOU" with an attachment "LOVE-LETTER-FOR-YOU.TXT.vbs" that people were encouraged to open. The message body is "kindly check the attached LOVELETTER coming from me." The sender line will be the address it was sent from. The user must download and execute the worm by clicking on it.
The worm may also come from an infected computer on the same IRC channel using mIRC. The worm will be in an infected HTML document named LOVE-LETTER-FOR-YOU.TXT.HTM downloaded into the IRC downloads folder. The user must access the .htm file to activate the worm.
Internet Explorer security settings do not allow scripts to access disk files and will display a warning when they try to. To work around this, the worm displays a message telling the user to give ActiveX control to the .htm file. If the user clicks on "Yes", the worm will infect the system. If the user clicks on "No", the worm reloads the message in an infinite loop until the user clicks on "Yes" to allow it to infect the system.
When the worm is executed, it copies itself as the files LOVE-LETTER-FOR-YOU.TXT.VBS and MSKERNEL32.VBS in the Windows_system_folder and WIN32DLL.VBS in the Windows directory. It creates its own key named MSKernel32 under the Local machine registry key that causes programs to run and adds the value MSKERNEL32.VBS to it. It also create a new Local Machine RunServices key named Win32DLL and adds WIN32DLL.VBS as a value to it, so it will run when the system boots, before the user even logs on.
The worm sets the Internet Explorer start page to one of four randomly chosen webpages so that it downloads the file WIN-BUGSFIX.EXE, a trojan. It then adds a registry key for it in the same manner that it registered its own files, so it will run at startup. After the WIN-BUGSFIX.EXE program has been run, it copies itself to the Windows system folder as WinFAT32.EXE, and replaces the WIN-BUGSFIX.EXE registry key with one for itself. This file obtains the system's logins, passwords, machine name, IP address, RAS information and some other information about the computer and sends it to firstname.lastname@example.org.
Loveletter searches for files to modify, mostly by replacing those files with a copy of itself. If the file has a .vbs or .vbe extension, it will simply overwrite the files. If they have the extensions js, jse, css, wsh, sct, or hta, it will overwrite the file as well as the extension, changing it to .vbs, but retaining the original name (program.js becomes program.vbs). For .jpg or .jpeg files, it overwrites them, retains the original file name and extension, but adds .vbs to the extension (picture.jpg becomes picture.jpg.vbs). Mp3 and mp2 files are not overwritten, but rather hidden.
Loveletter opens the Outlook email program, and scans for email addresses in the Address book. It sends the email with an attached copy of itself
The worm scans for the files mirc32.exe, mlink32.exe, mirc.ini, script.ini and mirc.hlp. If it finds one or more of these files, it will generate a new script.ini and place it in the directory where the files are found. The script contains instructions to send the file LOVE-LETTER-FOR-YOU.TXT.HTM to all users on the same IRC channel as well as a comment:
;mIRC Script" ; Please dont edit this script... mIRC will corrupt, if mIRC will ; corrupt... WINDOWS will affect and will not run correctly. thanks" ; ;Khaled Mardam-Bey ;http://www.mirc.com
The worm itself is a text script program, and it is spread in text source form. The worm's code may be easily modified by hackers, and as a result, there are many variants of the original worm. Most of them are just minor remakes and differ to the original worm just in details - there are message-fields text changed, different file names, different set of affected disk files extensions (for example, .BAT and .INI).
The subject, message body and attached file name in different variants appear as listed below (the first block belongs to original worm version):
|ILOVEYOU||kindly check the attached LOVELETTER coming from me.||LOVE-LETTER-FOR-YOU.TXT.vbs|
|Mothers Day Order Confirmation||
We have proceeded to charge your credit card for the amount of $326.92 for the mothers day diamond special. We have attached a detailed invoice to this email. Please print out the attachment and keep it in a safe place.Thanks Again and Have a Happy Mothers Day!
|fwd: Joke||- no message body in message||Very Funny.vbs|
|Susitikim shi vakara kavos puodukui...||kindly check the attached LOVELETTER coming from me.||LOVE-LETTER-FOR-YOU.TXT.vbs|
|Important ! Read carefully !!||Check the attached IMPORTANT coming from me !||IMPORTANT.TXT.vbs|
|Dangerous Virus Warning||
There is a dangerous virus circulating. Please click attached picture to view it and learn to avoid it.
|How to protect yourself from the IL0VEY0U bug!||Here's the easy way to fix the love virus.||Virus-Protection-Instructions.vbs|
|Thank You For Flying With Arab Airlines||Please check if the bill is correct, by opening the attached file.||ArabAir.TXT.vbs|
|Bewerbung Kreolina||Sehr geehrte Damen und Herren!||BEWERBUNG.TXT.vbs|
|LOOK!||hehe...check this out.||LOOK.vbs|
|Variant Test||This is a variant to the vbs virus.||IMPORTANT.TXT.vbs|
|Yeah, Yeah another time to DEATH...||This is the Killer for VBS.LOVE-LETTER.WORM.||Vir-Killer.vbs|
|I Cant Believe This!!!||I Cant Believe I Have Just Recieved This Hate Email .. Take A Look!||KillEmAll.TXT.vbs|
|New Variation on LOVEBUG Update Anti-Virus!!||
There is now a newer variant of love bug. It was released at 8:37 PM Saturday Night. Please Download the following patch. We are trying to isolate the virus. Thanks Symantec.
|IMPORTANT: Official virus and bug fix||
This is an official virus and bug fix. I got it from our system admin. It may take a short while to update your system files after you run the attachment.
|Bug and virus fix.vbs|
|Recent Virus Attacks-Fix||
Attached is a copy of a script that will reverse the effect of the LOVE-LETTER-TO-YOU.TXT.vbs as well as the FW:JOKE,
Mother's Day and Lituanian Siblings.
O UOL tem um grande presente para voce, e eh exclusivo. Veja o arquivo em anexo.
|BUG & VIRUS FIX||
I got this from our system admin. Run this to help pervent a ny recent or future bug & virus attack's. It may take a small while up update your files.
|MAJOR BUG & VIRUS FIX.vbs|
|FREE SEXSITE PASSWORDS||cHECK IT OUT ; FREE SEX SITE PASSWORDS.||FREE SEXSITE PASSWORDS.HTML.vbs|
|You May Win $1,000,000! 1 Click Away||kindly check the attached WIN coming from me.||WIN.vbs|
|Virus Warnings !!!||VERY IMPORTANT PLEASE READ THIS TEXT. TEXT ATTACHMENT.||very-important-txt.vbs|
|HOW TO BEAT VIRUSES||
kindly check the attached VIRUS INFORMATION coming from me. This is how you can be immune to any virus. It really helps alot!
|You must read this!||Have you read this text? You must do it!!||C:\NOTES.TXT.exe|
|New virus discovered!||
A new virus has been discovered! It's name is @-@Alha and Omega@-@.
Full list of virus abilities is included in attached file @-@info.txt@-@.
For the last information go to McAfee's web page
Please forward this mesage to everyone you care about.
|Wish you were Here!||Wish you were Here! Im having a great time!||Wish you were Here!.postcard.vbs|
This particular malware caused widespread e-mail outages. More than 45 million computers around the globe have supposedly been infected by various strains of the worm. The types of industries affected include stock brokerages, food companies, media, auto and technology giants, as well as government agencies, universities and medical institutions worldwide. The Ford Motor Company shut off its email system after being hit hard by the worm (General Motors was not directly affected by the worm, as they do not use Outlook at that company).
A partial list of others affected by the virus confirmed by CNET News.com were Silicon Graphics, the Department of Defense (including the Pentagon itself), Daimler-Chrysler, The Motion Picture Association of America, the Federal Reserve and Cox Cable. The worm was responsible for a denial-of-service attack on the official White House website. One web start-up reported losing 40 gigabytes of JPEG images. Estimates of the worm's damage are in between $8.75 billion and $10 billion.
This worm program was written by Onel A. de Guzman, a student of AMA Computer University in Makati, Philippines. The author of the worm has conceded that he may have released the malware by "accident". The worm was first discovered in Hong Kong.
Carnegie Mellon University Software Engineering Institute, CERT® Advisory CA-2000-04 Love Letter Worm
Kaspersky Labs, I-Worm.LoveLetter
Sharon Gaudin, Internetnews.com "Virus Damage Worst on Record for August". 2003.09.02
Paul A. Greenberg. E-Commerce Times, "'Love' Virus Damage Could Top $1B" 2000.05.05
Marcia Savage. ChannelWeb, Damage From Love Letter Virus Could Top $10 Billion. 2000.05.05